On Mon, Feb 2, 2009 at 10:05 AM, Andrew Butterfield
<Andrew.Butterfield at cs.tcd.ie> wrote:
> Martijn van Steenbergen wrote:
>>>>> To my naive mind this sounds
>>> suspiciously like the set of all sets, so it's too big to be a set.
>>>> Here you're probably thinking about the distinction between countable and
>> uncountable sets. See also:
>>>>http://en.wikipedia.org/wiki/Countable_set>> No - it's even bigger than those !
>> He is thinking of proper classes, not sets.
>>http://en.wikipedia.org/wiki/Class_(set_theory)
Yes, that's my hypothesis: type constructors take us outside of set
theory (ZF set theory, at least). I just can't prove it.
Thanks,
g